Film-makers on film: Thomas Vinterberg

"This is going to sound a bit of an excuse," says Thomas Vinterberg, "in the sense that Stalker was groundbreaking for me, but it's a while ago that I've seen it, so I cannot give you the deep analysis of it. Is that all right?" It's not a promising start – and yet one doubts that this serious-minded young Dane (writer-director of 1998's Festen and the ambitious new romance It's All About Love, now on general release) will disgrace himself. Certainly, there's nothing glib about his choice of film. One of the greatest works by the Russian filmmaker Andrei Tarkovsky, Stalker is not only the equal of the more famous Andrei Rublev (1969), Solaris (1972) and The Mirror (1975), but also shares these films' stark beauty, thematic complexity and blunt refusal to spoonfeed its audience.

It's set near a nameless city, in an unspecified time, yet one that has seen the mysterious creation of "the Zone", a room that can make anyone's deepest wishes come true. Despite the fierce security around it, a writer and a scientist, seduced by the Zone's reputation, enlist the help of a so-called Stalker (one of the few who can approach the Zone without coming to harm) to take them there. As they near it, through a bleak maze of buildings, the tension escalates fiercely. But it's their initial journey towards the Zone, via a primitive railway, that has always most impressed Vinterberg, largely because at no point in this protracted episode do actually you see what the trio themselves are seeing. "When I first saw it in '92, at film school," he says, "I remember that trip on the trolley as something that opened my world of cinematography.

"There were many things in this scene," says Vinterberg. "One of them is obviously the use of sound, giving me the perspective that what you don't see on screen is the whole life of the film - but I'll come back to that. I believe that the audience remember that trip with the trolley as if they had been watching a huge landscape themselves, but they've only seen faces experiencing it.

"It also taught me that film is dependent on development. It can never stop. They're on a trolley, getting deeper and deeper into something. So you can have a long, long shot without anything happening, and it's still development. That mechanical way that people normally develop film - cut to this, cut to that - was washed away. For me, these essentials of filmmaking were represented in that scene without me knowing it.''

Vinterberg did, however, realise this a few years later, when he was putting Festen together. Along with fellow Dane Lars von Trier, he was co-signatory of the Dogme95 manifesto, which aimed to pare filmmaking down to its barest essentials. The tale of a family gathering that unleashes the darkest secrets, Festen was the first (and still the best) film to be made according to Dogme rules, and was an instant classic.

"What I was talking about before," says Vinterberg, "about hiding the essentials, has become my basic rule with filmmaking. If you have a person who's supposed to be afraid in a scene, you ask the actor to try to give the impression that he's on top of things. And then, through a small crack in his behaviour, you reveal what it's really about. So, what the scene is about is what you don't see.''

Festen, I suggest, demonstrates this par excellence. "Oh yes. The story turns around a dead sister that you don't see. She was more visible in the script, but the more we cut her out, the more powerful she became. I think if Tarkovsky had made too many cuts to POV [point-of-view shots] of landscape, it would have been a flat scene. And if I had used all the material I had with the dead sister in Festen, she would just have been an actress playing a part. But now she became godly, you know?"

Stalker pulls off a similar trick in that, unlike almost every other science-fiction film ever made, the sci-fi is in the script. Where, say, George Lucas and Ridley Scott have seduced us with twinkling cities and thundering spacecraft, Stalker boasts no more high-tech sophistication than a Bakelite telephone and a faulty lightbulb. It's perhaps the clearest example in Tarkovsky's work of his suspicion of any surface sheen that might have titillated audiences – and might have earned him a lucrative, Hollywood-style career.

"Tarkovsky totally ignores that," says Vinterberg. "He's not a prostitute, he doesn't give a shit - and I adore him for doing that. 'I'm not going to follow you,' he's saying. 'You have to follow me.' And he invites you to think: what does it mean to go to the Zone? What happened there? What is happiness? How are you looking for it? It's inspirational.

"And then," he adds, "there's this dog, completely unexplained. Why a dog? But it works, doesn't it? It's magical. I'm sure if I'd been to university doing a degree on film, I'd know a lot more about that dog. But I just like it.''

Our time is now up, and we shake hands. "I hope all that was all right," asks the director who feared he would have little of interest to say.

Thomas Vinterberg, writer, director

Born: Copenhagen 1969

Selected films: Festen (1998), It's All About Love (2004)

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